Water-logged easterners may not believe it, but much of the country is unseasonably dry.
Moisture levels are below average in Colorado, Arizona, New Mexico, Montana, and Wyoming, and much of the Great Plains from Oklahoma to North Dakota is experiencing drought as well. In all, one-fourth of the US is facing moderate-to-extreme drought conditions, which brings the threat of fire.
"The long-term moisture deficits and high fuel loadings are producing critically high fire potential, particularly in the higher elevation timber," researchers at the University of Arizona's Institute for the Study of Planet Earth reported recently.
As a result, the number of fires and the acreage burned have set 10-year highs. The number of acres burned so far is more than twice the average over the past decade, according to the National Inter-agency Fire Center in Boise, Idaho. One 40,000-acre fire even threatened the University of Nevada Fire Science Academy, giving students the kind of on-the-job training they hadn't counted on.
Wildfire detection and management have gone through a renaissance of sorts in recent years, experts say. Rotating digital cameras are replacing human lookouts posted in lonely mountain towers. Satellites, computers, remote automated weather stations, and lightning strike detectors are among the new tools used to monitor, map, and model fires.
"It's really giving people more comfort in their ability to predict fire behavior," says veteran firefighter Timothy Ingalsbee, executive director of Firefighters United for Safety, Ethics and Ecology (FUSEE) in Eugene, Ore. This year's high fire danger was predictable as well, he says. A wet season allowing lots of surface vegetation to grow has been followed by an unusually dry season where all that vegetation is available to burn.
With more people moving into what's called the "wildland-urban interface," coordinating fire-fighting efforts among agencies becomes more complicated and contentious.
The recent political focus on immigration is an issue since many Hispanics are contract firefighters. No one knows how many people are in the US illegally, and cracking down on illegal immigrants, as well as the deployment of National Guard troops overseas, has governors in fire-prone states concerned that they may not have sufficient resources to fight fires this summer.
Postfire salvage logging is a concern, too. Proponents say such logging, followed by replanting, helps reduce the risk of future fires and allows for quicker regeneration. But many wildland firefighters disagree.
"Timber plantations thick with even-aged nursery-grown conifers, untreated logging slash, and invasive weeds pose some of the greatest hazards to firefighters," members of FUSEE wrote in a letter to Congress this spring.
"Wildfires are prone to sudden 'blow-ups' when they enter this volatile mix of hazardous fuel," warned this group, whose members include current and retired wildland firefighters.
In addition to more sophisticated equipment, firefighters increasingly use techniques other than the traditional goal of dousing every blaze by 10 a.m. the next day. One is called "wildland fire use," or managing (some say "herding") remote fires without aggressively suppressing them. The idea is to use fire as a natural force to restore and maintain the ecological health of forests – clearing areas in a controlled way to reduce the risk of future catastrophic fires.
Though fire experts now are better able to predict wildfires and respond accordingly, many see global climate change as a wild card.
"That's really upending what we used to call normal fire behavior and activity," says Dr. Ingalsbee, who teaches the social and environmental aspects of wildfires at the University of Oregon. "We could be entering a period of extended drought punctuated by very extreme storm events."
Most wildfires are caused by lightning in summer thunderstorms.
A big part of the danger comes with suburbs pushing farther into the wildland-urban interface where homes are surrounded by trees and shrubs that can fuel fires, says Rich Fairbanks, who spent 32 years as a US Forest Service firefighter. This is especially true in canyons where upslope winds blow stronger and push fires along – the "venturi effect," or acceleration caused by restriction.
"We're building our houses on steeper and steeper ground ... in places where fire has much more potential for real active behavior that goes beyond the capability of crews to put them out," says Mr. Fairbanks, who now works on local and regional fire management issues for the Wilderness Society. "That is a huge problem in the West."
At the same time, says Fairbanks, some communities and agencies have begun to respond. New zoning ordinances address the need to trim shrubbery away from structures while ensuring enough room for fire trucks to turn around. Building codes require construction materials more suitable to fire-prone areas: less-flammable roofing materials (rather than cedar shakes, for example) and double-glazed windows less likely to blow inward allowing fire to sweep through a house.
"There are counties in southern California with excellent codes for this kind of thing, and they're moving to make them stricter," says Fairbanks. "Oregon has a wildland-urban interface act that I think is excellent."
"It's a really good start," he says, "but it takes time."
As of Tuesday, the National Fire Information Center was reporting 442 new fires, 14 of those classified as "large" (at least 300 acres) bringing the total of active large fires to 29.